Fairy Tail and Naruto are favourites? Then these are definitely in
1) Busou Renkin
2) Full Metal Alchemist - Brotherhood is preferable, but the 1st series is definitely good recommendation as well.
3) Soul Eater
4) Classic choice - What, no Dragon Ball yet?
I cannot vote for OP (I cant stand the art), nor can I vote for Hunter x Hunter (I hate Gon with a passion!), but these 2 should be within your required specification as well
Samurai Champloo, Seirei no Moribito and Samurai 7 could be considered as candidates as well, but they would be considered lacking in humor department. But do watch the first 2 for awesome story and swordfight choreography ..